ath9k: queue null frames in case of MCC

While mac80211 using null frames when connection polling,
we should queue this frames while NOA could be there, and
AP, P2P_GO could be not present.

Without this patch, with no traffic we often saw disconnections
while we try to send nullfunc when AP/GO wasn't present.
Signed-off-by: NJanusz Dziedzic <janusz.dziedzic@tieto.com>
Signed-off-by: NKalle Valo <kvalo@qca.qualcomm.com>

drivers/net/wireless/ath/ath9k/xmit.c

@@ -2331,6 +2331,12 @@ int ath_tx_start(struct ieee80211_hw *hw, struct sk_buff *skb,
 
 	queue = ieee80211_is_data_present(hdr->frame_control);
 
+	/* If chanctx, queue all null frames while NOA could be there */
+	if (ath9k_is_chanctx_enabled() &&
+	    ieee80211_is_nullfunc(hdr->frame_control) &&
+	    !txctl->force_channel)
+		queue = true;
+
 	/* Force queueing of all frames that belong to a virtual interface on
 	 * a different channel context, to ensure that they are sent on the
 	 * correct channel.